Berrien County’s first case of West Nile virus this year has been diagnosed.

The County Health Department says an adult woman became ill in late July and showed symptoms of the virus.

With the mosquito population remaining active into the fall months in Southwest Michigan, officials urge people to take precautions to protect themselves from mosquito bites.

Michigan has seen outbreaks of West Nile virus every year since 2002.

Roughly one in five infected people will have a mild illness that could include fevers, vomiting, joint pain, rash or other symptoms.

About one in 150 will have a serious illness. People over the age of 60 are more susceptible to severe symptoms of West Nile.